More particularly, the invention relates to installing a plastic service pipe in an existing steel service pipe. Typically, the service pipe is a gas service pipe but the invention is not limited to such an application but is applicable to water, fluid waste disposal or other service pipes, for example.
A method is known for replacing an existing steel service pipe extending from a main to a meter. The meter is removed and a plastic service pipe is inserted through the open end of the steel service pipe and advanced up to a point adjacent the main. The plastic pipe has a sealing head at its leading end. Fluid sealant is fed to the space between the plastic pipe and the steel service pipe. The sealing head sealingly engages the interior of the steel service pipe and has a seal. When the fluid sealant has solidified the seal is broken by the pointed end of a flexible rod inserted through the plastic pipe.
In such a known method the plastic service pipe has a cylindrical wall. The plastic service pipe has some flexibility allowing it to be inserted past a swept bend between the vertical and horizontal runs of the steel service pipe.